code: def test_hidden_callback(self):
      try:
          self.module.hidden_callback(2)
      except Exception as msg:
          assert str(msg).startswith("Callback global_f not defined")
  
      try:
          self.module.hidden_callback2(2)
      except Exception as msg:
          assert str(msg).startswith(
              "cb: Callback global_f not defined"
          )
  
      self.module.global_f = lambda x: x + 1
      r = self.module.hidden_callback(2)
      assert r == 3
  
      self.module.global_f = lambda x: x + 2
      r = self.module.hidden_callback(2)
      assert r == 4
  
      del self.module.global_f
      try:
          self.module.hidden_callback(2)
      except Exception as msg:
          assert str(msg).startswith("Callback global_f not defined")
  
      self.module.global_f = lambda x=0: x + 3
      r = self.module.hidden_callback(2)
      assert r == 5
  
      # reproducer of gh18341
      r = self.module.hidden_callback2(2)
      assert r == 3
  
imports: import math
  import textwrap
  import sys
  import pytest
  import threading
  import traceback
  import time
  import numpy
  from numpy.testing import IS_PYPY
  from .None import util
label_desc: Use image node_id 7 for calling the TestF77Callback obj's underlying member method code with example usage: obj.test_hidden_callback() without return types